1. Field
The one or more aspects of the exemplary embodiment generally relate to automated storage and retrieval systems for warehouses and stores.
2. Brief Description of Related Developments
Automated storage and retrieval systems are desired such as for warehouses and stores because of the potential and imagined efficiencies that such systems present. Examples of such systems include storage structure that define one or more levels of storage, locations and automated transport systems (such as carts, fork lifts, other independent automated vehicles or rovers, elevators, linearly continuous transport devices such as conveyors, roller beds, etc.) distributed or disposed to transport store units to and from store locations throughout the storage array. Realization of the efficiency potential presented by such systems may at times involve disparate factors that may act to mitigate the potential benefits of other factors. For example, dynamic allocation of storage locations in the array, with appropriate dynamic distribution of autonomous independent vehicles or rovers capable of effecting store unit placement in accordance with such allocation may provide for increased efficiencies in storage throughput. Similarly, greater transport speeds and freedom of movement of rovers may provide increased efficiency, and greater density of storage locations from having more storage levels or more closely spaced levels, or rack aisles may provide improved storage efficiency of the storage space. As may be realized upon further consideration certain manipulation or actions to optimize efficiencies of some factors may be in opposite or detract from optimal efficiencies of other factors resulting an overall efficiency of the ASRS that is minimally improved (if at all) despite significant efficiency gains in one factor or another. Overall efficiency of the ASRS, which may be considered generally to include factors dealing with how efficiently store units can be stored in the storage space (and may be thought to represent cost of storing a store unit in the ASRS and otherwise referred to as storage space efficiency) and factors dealing with how efficiently the store units may be moved, such as by the automated transport system, into the storage space, though the storage space to and from storage locations, in the storage space, and back out from the storage space (which may be thought of as representing the cost of moving a store unit in the ASRS, and referred to as transport efficiency). An ASRS with an improved control system that maximizes both storage space efficiency and transport efficiency is desired.